(a) Technical Field
The present disclosure relates to a system for controlling a radiator flap of a vehicle. More particularly, it relates to a system for controlling a radiator flap of a vehicle which simplifies the opening and closing of a radiator flap to reduce manufacturing cost and expand use to a wider range of vehicles.
(b) Background Art
As oil price rises and air pollution and global warming grow as a global problem, a considerable amount of attention has focused on increasing fuel efficiency of a vehicle. The fuel efficiency of vehicles has been improved using a number of different methods. One method involves using an electric motor or a fuel cell instead of traditional petroleum gasoline. Other possible methods involve improving fuel efficiency of an existing internal combustion engine or reducing air resistance while driving. Among these methods, the reducing of air resistance includes mounting a controllable radiator flap to a front surface of a vehicle and controlling a speed of a cooling fan, which improve fuel efficiency by maintaining an appropriate temperature within an engine.
The cooling fan controls a speed by receiving a speed signal from an engine management system (EMS) by a pulse width modulation (PWM) control, and the radiator flap, or an active air flap (AAF), uses an actuator capable of controlling the opening and closing of the radiator flap. Accordingly, the existing technology of controlling the cooling fan and the radiator flap is applied to luxury or environmentally-friendly vehicles due to substantial manufacturing costs. Further, the technology used to control the radiator flap is more complex than the technology used to control the cooling fan, so the radiator flap and the cooling fan are controlled separately.
The radiator flap is generally installed between a bumper and a radiator at a front part of the vehicle and can be opened and closed as needed. When the flap is closed, an air resistance coefficient decreases, causing air resistance to decrease thus improving fuel efficiency. When travelling at a substantially high speed and the flap remains closed to improve fuel efficiency, a temperature of a coolant of an engine and a main component disposed within the engine increases. When the temperature of the coolant and the main component increase to a predetermined value, or greater, the flap opens to decrease the temperature within the engine. Therefore, when the temperature of the coolant of the engine is relatively high, the radiator flap opens to reduce the temperature of the coolant. Alternatively, when the temperature of the coolant of the engine is relatively low, the radiator flap closes to reduce air resistance.
The above information disclosed in this section is merely for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.